About 1 in 8 veterans using VA primary care clinics meets criteria for PTSD. This underscores the importance of having VA providers who are highly skilled in the implementation of the best PTSD treatments available. Prolonged exposure (PE), a treatment protocol developed by Dr. Edna Foa (a key investigator on this project), was recently identified as a "best practice" approach by the Institute of Medicine. A national initiative is ongoing to train VA providers in this approach, funded by the Office of Mental Health Services in the VHA Central Office. The availability of high-quality, low-cost training tools for VA providers is therefore of high significance. To this end, this application describes a plan to develop PE-Web, an innovative, 8-10 hour Web-based training protocol for VA providers that has the capacity to strengthen providers'preparation to deliver PE to veterans with PTSD with a high level of fidelity. Our investigative team is well positioned to develop and evaluate PE- Web, having been highly successful in development of other Web-based clinician-training protocols relating to traumatic stress populations (TF-CBTWeb, CTGWeb). TF-CBTWeb, launched in October 2005, has already logged over 29,000 registered learners representing all 50 states and 88 countries. The proposed project, in addition to supporting the development of PE-Web, will support efforts to preliminarily evaluate it with 100 VA providers who had previously received initial training in PE. We will evaluate PE-Web using randomized controlled methods. If findings are supportive of PE-Web as a valuable VA provider-training tool, numerous avenues for disseminating this low-cost resource to VA providers will be explored.